During the mechanical action that involves the soil removal or soil disruption, the adhesion thereof to the agricultural tools play a major role, affecting both work quality and efficiency of the process. Certain fundamental tasks such as planting or seeding are preferably made with high water content in the soil as it is favorable for rapid germination and crop emergence. However, under these conditions, adhesion of soil to the distribution train parts of the seeder, such as blades (Coulters), tillers, furrow openers and seed furrow closers may affect the correct placement of the seed into the furrow reducing the efficiency of implantation. The labor should often be stopped due to clogging of the planter, drill, or seeders even though the soil conditions allow the transit of equipment.
The reduction of soil adhesion to working parts or tools would allow, firstly, to achieve opening and closing of furrows that render a suitable distribution and germination of seeds and secondly, to get an earlier labor start by increasing the time available to perform the tasks. Having more time means increasing the opportunity to work, which would allow reducing the power required to perform the same amount of work and reduce both operating costs and application of surface loads leading to the densification of the soil.
The foregoing also applies to equipment for addition of fertilizers or pesticides into the soil, by means of disk harrows prior to crop seeding or by means of row crop cultivators after crop emergence.
Special consideration must be given to plowing or tillage or subsoiling carried out by scarifiers, chisels or subsoilers. These labors generate a deep soil disturbance and for this reason are the ones which demand the highest levels of power. In this case, the adhesion of soil to working tools makes the interaction between them be produced in a soil-soil interface. Reducing said adhesion means replacing the soil-soil friction with friction between metal and soil, which can reduce the energy requirement of the labors.
For all, the above, if the adhesion is reduced not only can it be reduced the traction or drawing force on the tool with a consequent reduction in fuel consumption, but also the time window for carrying out plowing or tillage can be extended by reducing the required power.
In recent decades, biomimetics, i.e. the designing, building, testing and maintaining artificial systems which are inspired by living systems, has opened a fruitful field of investigation for applications and engineering solutions. These innovations inspired by nature originally derived from the work of Leonardo da Vinci on the study of bird flight. Given the characteristics of the subject matter, however, the first patent inspired by biomimetics was filed not earlier than the mid-1950s, corresponding to the final design of Velcro, in 1955, by George de Mestral, a Swiss engineer. Today the analysis of functional and structural principles of certain biological surfaces allows their use in artificial systems made by man. Examples include the effect of shark, skin to generate anti-friction surfaces (surface of the fuselage of the Airbus 380), the moth-eye effect to achieve anti reflection surfaces (solar cells), the Gecko effect for the development of dry adhesion surfaces (smart adhesives) and the lotus effect (Lotus plant, Nelumbo nucifera) to produce self-cleaning ultra-hydrophobic surfaces (Lotusan paints).
Patent application US 2009/0101370 A1 (Tasovski) discloses a bulldozer blade with a soil interaction surface with an array of anti-adhesion biomimetic protrusions that project out of the base surface. The protrusions are arranged in a rectangular pattern.
European patent application EP 2407671 A1 (Tei et al.) discloses a fan blade with an array of dimples in the vicinity of the edge in order to change a boundary layer from laminar flow to turbulent flow. It deals only with aerodynamic issues.
U.S. Pat. No. 5,172,770 (Moyle) discloses an agricultural share with depressions in the vicinity of the edge in order to reduce the “footprint” area of the share. No mention is made to a critical or advantageous specific depression array.
U.S. Pat. No. 6,532,855 B1 (Ward et al.) discloses a saw blade having a multiplicity of discrete dimples of different shape and randomly arranged. No mention is made to a critical or advantageous specific depression array.
U.S. Pat. No. 6,739,991 B1 (Wardropper) discloses apparatus and method for making a ceramic arrowhead blade having improved features regarding strength, weight and corrosion resistance, the blade may have dimples on its surface. The dimples are arranged in a rectangular pattern and no mention is made to a critical or advantageous specific depression array.